Chain grate



Feb. 23 1926.

w. M. DUNCAN CHAIN GRATE Filed August 18, 1921 2 Sheets-Sheet l \\IInventor.-

2 Sheets-Sheet 2 ill! INUBHZOI":

WM DDncan Feb. 23 1926.

W. M. DUNCAN CHAIN GRATE Filed August 18, 1921 reamed Feb. 23, teen.

WILLIAM M. DUNCAN, OF ALTON, ILLINOIS.

CHAIN GRATE.

Application filed August 18, 1921. Serial No. 493,198.

To all whom it may concern:

Be it known that I, IVILLIAM: M. DUNCAN, a citizen of the United Statesof America, anda resident of Alton, in the county of Madison and Stateof Illinois, have invented certain new and useful Improvements in ChainGrates, of which the following is a full, clear, and exact description,reference being had to the accompanying drawings, forming a part of thisspecification. 7

This invention relates to improvements in chain grates, the main objectbeing to produce a chain grate adapted to receive very fine fuel withoutundue loss of the fuel at the draft passageways in the grate. In a chaingrate, the grate links should be separated from each other to providepassageways for the admission of draft to the fuel. The'problem ofadmitting adequate draft and at the same time preventing free escape offine fuel, is a difficult one that has never been entirely solved, andmy object is to produce a chain grate from which these results can. bemost effectively obtained.

In the preferred form of the invention, the flexible chain grate isprovided with piv otally connected grate links having longitudinalbaffle ribs which obstruct the fuel tending to pass through the grate.30'

These baffle ribs are so formed that the draft can pass freely to thefuel, and they do not in any wayinterfere with the pivotal movevments ofthe links. Furthermore, the battles are so arranged. that any fineparticles of fuel entering between the links Wlll be d1scharged when thellnks turn on their pivots,

so the links are repeatedlycleaned while the grate is in motion. 7

A further ob ect is to prevent free escape of ashes through the gratestructures, and

.this is of course accomplished by the means for preventing free escapeof fine particles of fuel.

A further ob ect is to provide an effectivemeans for preventlng thedraft from flowinglengthwise of the grate at points beings wherein isshown the preferred embodiment of the invention. However, it is .tO beunderstood that the invention comprehends changes, var1at1ons andinodihcatlons which come within the scope of the claims hereuntoappended. Fig. 1 is a top view, partly in section, illustrating severalrows of grate links embodying the features of this invention, thesection being in the plane of the pivot rods. Fig. II is aside elevationof the structure shown in Fig. I, some of the links being shown by dotand dash lines to illustrate the pivotal motion of the links.

Fig. III is a vertical section taken approximately on the line III-IIIin Fig. II.

Fig. IV is a vertical section taken approximately on the line IVIV inFig. II, some of the parts distant from said line being omitted.

Fig. V is a perspective view showing one side of the new grate link.

VI is a perspective view showing the other side of the link.

The links shown by Figs. I, II, III and IV an be made exactly alike, andone of these links is shown by Figs. V and VI. I will describe one ofthe links and then point out the manner in which the several linkscooperate with each other.

Each link is provided with a longitudinal battle rib it extendingapproximately from end to end of the link and projecting from the topmargin of one of the side faces of the link. Each link also has a lowerlongitudinal baflie rib B extending from end to end of the link andprojecting from the other side face thereof. Fig. IV shows that the ribB at one side of the link is lower than the rib A at the other side.Transverse grooves l are formed in the top face of the link, as shownmost clearly by Figs. V and VI, and these grooves are continued down theside faces of the battle rib A. The lower portion of each link isprovided with a pair of pivot receiving openings-2 (Fig. V) formed nearthe ends of the link. The bottom face of the rib A is provided withcurved portions 3 coaxial with the respective openings 2, and the battlerib B has curved top faces 4: coaxial with these open ings. designatespivot rods passing through the openings 2, so as to pivotally connectthe several links.

lVhen the links are assembled, as shown by Fig. IV, the baiiie ribsi'f-i overlap the ribs I5, and the bottom face of each rib A isseparated from the top face of a lower rib B. Each rib B is separatedfrom the side face of the next adjacent link, so the draft can "links.

pass'fr'eely between the links and escape to th fuel supported on thetop faces of the links.

Figs. I and 11 show that the links are arranged in straight rowswhichare pivotally connected by the rods 5 to provide a flexible chaingrate. For reasons well understood in this art, the links are movableabout the axes ofthe pivot rods as suggested by the dot and dash linesin Fig. H. and since the lapped faces of the baffle ribs A and B arecoaxial with the respective pivots, it will be understood that theseribs donot in any way interfere with the pivotal movements ofthe Thebaffles A in each row of links overlap the battles B in the nextadjacent row so asto obstruct fine particles of fuel, or ashes,tendingto pass between the sides of the links. f In the grate structureI haveshown, the links ofadjacent rows are staggered relative to eachother. as shown most clearly by Fig. I, so that the links in aninterposed row are not in alinement with the links at opposite sidesthereof. In other words, the longitudinal batl'le rib A of each linkoverlaps the baffle ribs B on two of the links in the next adjacent row,but the ribs are so formed that each link can turn freely on its twopivot rods 5.

I will now refer to vertically disposed battle ribs which impede aircurrents tendcal'batlle rib 8 extending from the longitudinal rib A. tothe lower edge of the link. The opposite side of each link is providedwith a vertical battle rib Slextending from the rib-'3) to the loweredge of the link. \Vhen the links are assembled, one of the verticalribs 8 lies adjacent to one of the ribs S), as shown by Figs. I and Ill,and these adjacent ribs lie betwen the ends of two links. They preventthe fuel from dropping between the adjacent ends of the links, and theyimpede airv currents tending 1 Each (Figs. lll'and V) which extends intoa recess at the top of a I'll 9. Each rib 8 1s thus extended to overlapa rib 9, and the overlapping portions lie immediately below the spacebetween the ends of two links. The ribs 8 and 9 on anyone of the linkslie midway between the ends of the links, and these ribs are extendedfrom the several rows'of links, so that any two companion ribs 8 and 9extend across'an interposed row of the links at'points directly belowthe adjacent ends of two linksin the interposed row.

I claim: "1. A flexible chain grate comprising rows of pivotallyconnected grate links, each of tudinal said links having on one of itssides an u per longitudinal baliie rib formed at its top margin andextending approximately from end to end of the link, each link alsohaving on its opposite side a lower longibafllej extending approximatelyfrom end to end of the link, the lower longitudinal batlleson the'linksin one row being overlapped by the upper longitudinal bafile ribs on thelinks in-the next adjacent row, and said lower longitudinal batlies'being separated from the overlapping upper longitudinal battles toprovide for the de- 7 livery of draft between the battles.

2. A flexible chain grate con'iprising rows of pivotally connected gratelinks, each of said links having on one of its ..icles an upperlongitudinal baffle rib formed at its top margin and extendingapproximately from end to end of the link, each link also having on itsopposite side a lower longitudinal baffle extending approxin'iately fromend to end of the link, the lower longitudinal. battles on the link inone row being overlapped by the upper longitudinal baffle ribs on thelinks in the next adjacent row, each lower longitudinal baliie having atop face adjacent to but separated from the bottom face of an upperlongitudinal battle rib, and said faces having curved portionsapproximately coaxial with the correspond ing connecting pivots. i

3. it'grate link having an upper longi tudinal battle at the upper edgeof one of its side faces, and a lower longitudinal battle at the upperportion ofits other side face- 4. A grate link having anupperlongitudinal bazllle at the upper edge of one of its side faces, and alower longitudinal baffie at the upper portion ofits other side face,said link also having pivot-receiving openings,'and port-ions of saidlongitudinal baffles being approximately co-axial with the respectiveopenings.

oil grate link having an upper longitudinal baffle atthe upper edge ofone of its side faces, and a lower longitudinal baftie at the upperportion of its other side face, the lower portion of said link havingpivot-receiving openings, said upper longitudinal baffle having bottomfaces approximately co-axial with the respective openings, and saidlower longitudinal baffie being provided with top faces approxi-' beingstaggered relative to each other so that the links 111 an interposedrow'are not in transverse alinement with the links at opposite'sidesthereof, the links in each of said rows being provided with transverse 7battle ribs which extend between end port-ionsof the links man ad acentrow, so

tions of the links in an adjacent row, so

as to impede air currents tending to flow longitudinally of the grate,the upper end of each of said baiiies being provided with a lateralextension overlapping another of said bafiles.

8. A chain grate comprising endless rows of grate links, the links ofadjacent rows being staggered relative to each other so that the linksin an interposed row are not in transverse alinement with the links atopposite sides thereof, the links in each of jacent ends of two of saidlinks.

9. A grate link having oppositely disposed baflie ribs on its sidefaces, said baiile ribs extending from the lower margin of the link tothe upper portion thereof, one of said ribs having a lateral extensionand the other rib having a recess formed opposite to said lateralextension, said extension being adapted to extend into a recess in a ribof an adjacent grate link and said recess being adapted to receive anextension on a rib of an adjacent grate link when the grate link forms apart of an assembled grate.

10. A flexible chain grate comprising rows of pivotally connected gratelinks, the links of one row being provided with longitudinal bafiie ribsoverlapping portions of the links in the next adjacent row, each of saidlinks also having transverse bailles overlapping portions of the linksin another row.

11. A flexible chain grate comprising rows of pivotall connected gratelinks, each of the links in one of said rows being provided with alongitudinal ballle rib formed at its upper margin andextendingapproximately from end to end of the link. and each link in thenext adjacent row being provided with a longitudinal baffle rib at itsupper portion overlapped by two of the longitudinal ribs of the otherrow, so as to prevent free escape of fuel between the links, each ofsaid links also having a transverse baflle rib extending from itslongitudinal battle rib to the lower margin of the link.

In testimony that I claim the foregoing I hereunto aliix my signature.

lVlLLIAM M. DUNCAN.

